1. Field of the Invention
The present invention relates to a liquid crystal display device, by which light leakage is reduced by distributing a force applied to a liquid crystal display panel by a top cover.
2. Discussion of the Related Art
Generally, a liquid crystal display (LCD) as one of various flat panel type displays has visibility better than that of a cathode ray tube (CRT). The LCD also has lower power consumption and a lower exothermic quantity than those of the CRT having the same screen size. Therefore, the LCD has recently been identified as a next generation display device for a mobile phone, computer monitor and television.
Such an LCD has an operational principle of displaying an image via the liquid crystal substance, which is an intermediate substance between liquid and solid. The liquid crystal substance is injected in between a pair of thin glass panels whose surfaces are specially treated. By varying alignment of liquid crystal molecules with a voltage difference of electrodes between the upper and lower glass panels, the light transmission through the liquid crystal substance will change. Since the panels to display characters thereon are unable to emit light, the LCD needs a light source such as a lamp to make display contents visually recognizable.
Generally, a backlight assembly is provided as a light source to a back side of an LCD module used as a screen display device of a portable computer such as a notebook computer.
FIG. 1 is a perspective view of a module of an LCD according to a related art. FIG. 2 is a cross-sectional view of the module along a bisected line of I-I′ in FIG. 1.
Referring to FIGS. 1 and 2, a module 100 of an LCD includes an LCD panel 110 at a front side to display a video, a backlight assembly 120 at a rear side of the LCD panel 110 to provide a light source for the LCD panel 110, a mold frame 117 supporting the backlight assembly 120, a top cover 119 supporting an edge of a front side of the LCD panel 110, and a rectangular frame type bottom cover 118 enclosing a lower surface of the backlight assembly 120 to install the backlight assembly 120 therein and to be assembled to the top cover 119.
The backlight assembly 120 includes a fluorescent lamp 111 at one side of the LCD panel 110, a lamp housing 112 fixing the fluorescent lamp 111 thereto to condense light emitted from the fluorescent lamp 111 into a light-guide plate 113, a light-guide plate 113 converting incident light from the fluorescent lamp 111 to be a plane light source, optic sheets 115 and 116 attached to the light guide plate 113 to raise efficiency of light incident on the LCD panel 110, and a reflective sheet (reflector) 114 attached to a backside of the light-guide plate 113 to reflect light from a rear side of the light-guide plate 113 toward the LCD panel 110.
A receiving space is provided within the mold frame 117. The lamp 111 of the backlight assembly 120 is installed within the mold frame 117 along one side edge of the backlight assembly 120. Since the lamp 111 is electrically operative, wires are connected to both end portions of the lamp 111 to supply power from outside.
The backlight assembly 120, including the reflective sheet 114, the light-guide plate 113 and optic sheets 115 and 116, is inserted in the mold frame 117 to be fixed thereto. In addition, the LCD panel 110 is situated over the sheets to display information using the light transferred from the backlight assembly 120.
Coupling recesses are formed at the rear side of the bottom cover 118 opposed to the mold frame 117 to leave a predetermined distance from each other. In addition, the bottom cover 118 is bent to have a ‘’ shape to enclose one lateral side and front side of the mold frame 117. Moreover, the bottom cover 118 is formed of an aluminum (Al) based material.
A predetermined edge area of the top cover 119 is bent to prevent the LCD panel 110 from being separated from the mold frame 117. In addition, the top cover 119 is assembled to the bottom cover 118.
FIG. 3 is a layout of a top view of the LCD according to the related art, in which the LCD panel pressurized by the top cover is shown.
Referring to FIG. 3, the top cover 119 is configured to pressurize an upper panel 104 of the LCD panel 110. A reference “A” of the upper panel indicates an area of the pressurized top cover.
However, if the upper panel having a color filter thereon is pressurized, the pressure is concentrated on one side only. Hence, light leakage takes place in the LCD panel to appear on the LCD panel as a shape of the bright line.